Extra clearance 440 Main Bearings

Go ahead and run .001 clearance and 0W20 oil and when you spin a main and waste the block I'll still be running mine 7000 rpm with straight 40W
agreed, street and race are totally different requirements, I'm running 7200rpm and 14-1 compression, like you say you'll definitely spin a bearing with standard clearance. These old girls aren't manufactured to the tolerance of the new gen engines that will live with tighter clearances